/**

 * FreeRDP: A Remote Desktop Protocol Implementation

 * Simple HTTP client request utility

 *

 * Copyright 2023 Isaac Klein <fifthdegree@protonmail.com>

 *

 * Licensed under the Apache License, Version 2.0 (the "License");

 * you may not use this file except in compliance with the License.

 * You may obtain a copy of the License at

 *

 *     http://www.apache.org/licenses/LICENSE-2.0

 *

 * Unless required by applicable law or agreed to in writing, software

 * distributed under the License is distributed on an "AS IS" BASIS,

 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.

 * See the License for the specific language governing permissions and

 * limitations under the License.

 */

#include <freerdp/config.h>

#include <freerdp/utils/http.h>

#include <winpr/assert.h>

#include <winpr/string.h>

#include <openssl/bio.h>

#include <openssl/ssl.h>

#include <openssl/err.h>

#include <freerdp/log.h>

#define TAG FREERDP_TAG("utils.http")

static const char get_header_fmt[] = "GET %s HTTP/1.1\r\n"

                                     "Host: %s\r\n"

                                     "\r\n";

static const char post_header_fmt[] = "POST %s HTTP/1.1\r\n"

                                      "Host: %s\r\n"

                                      "Content-Type: application/x-www-form-urlencoded\r\n"

                                      "Content-Length: %lu\r\n"

                                      "\r\n";

#define log_errors(log, msg) log_errors_(log, msg, __FILE__, __func__, __LINE__)

static void log_errors_(wLog* log, const char* msg, const char* file, const char* fkt, size_t line)

{

  const DWORD level = WLOG_ERROR;

  unsigned long ec = 0;

  if (!WLog_IsLevelActive(log, level))

    return;

  BOOL error_logged = FALSE;

  while ((ec = ERR_get_error()))

  {

    error_logged = TRUE;

    WLog_PrintTextMessage(log, level, line, file, fkt, "%s: %s", msg,

                          ERR_error_string(ec, NULL));

  }

  if (!error_logged)

    WLog_PrintTextMessage(log, level, line, file, fkt, "%s (no details available)", msg);

}

static int get_line(BIO* bio, char* buffer, size_t size)

{

#if !defined(OPENSSL_VERSION_MAJOR) || (OPENSSL_VERSION_MAJOR < 3)

  if (size <= 1)

    return -1;

  size_t pos = 0;

  do

  {

    int rc = BIO_read(bio, &buffer[pos], 1);

    if (rc <= 0)

      return rc;

    char cur = buffer[pos];

    pos += rc;

    if ((cur == '\n') || (pos >= size - 1))

    {

      buffer[pos] = '\0';

      return (int)pos;

    }

  } while (1);

#else

  if (size > INT32_MAX)

    return -1;

  return BIO_get_line(bio, buffer, (int)size);

#endif

}

BOOL freerdp_http_request(const char* url, const char* body, long* status_code, BYTE** response,

                          size_t* response_length)

{

  BOOL ret = FALSE;

  char* hostname = NULL;

  const char* path = NULL;

  char* headers = NULL;

  size_t size = 0;

  int status = 0;

  char buffer[1024] = { 0 };

  BIO* bio = NULL;

  SSL_CTX* ssl_ctx = NULL;

  SSL* ssl = NULL;

  WINPR_ASSERT(status_code);

  WINPR_ASSERT(response);

  WINPR_ASSERT(response_length);

  wLog* log = WLog_Get(TAG);

  WINPR_ASSERT(log);

  *response = NULL;

  if (!url || strnlen(url, 8) < 8 || strncmp(url, "https://", 8) != 0 ||

      !(path = strchr(url + 8, '/')))

  {

    WLog_Print(log, WLOG_ERROR, "invalid url provided");

    goto out;

  }

  const size_t len = WINPR_ASSERTING_INT_CAST(size_t, path - (url + 8));

  hostname = strndup(&url[8], len);

  if (!hostname)

    return FALSE;

  size_t blen = 0;

  if (body)

  {

    blen = strlen(body);

    if (winpr_asprintf(&headers, &size, post_header_fmt, path, hostname, blen) < 0)

    {

      free(hostname);

      return FALSE;

    }

  }

  else

  {

    if (winpr_asprintf(&headers, &size, get_header_fmt, path, hostname) < 0)

    {

      free(hostname);

      return FALSE;

    }

  }

  ssl_ctx = SSL_CTX_new(TLS_client_method());

  if (!ssl_ctx)

  {

    log_errors(log, "could not set up ssl context");

    goto out;

  }

  if (!SSL_CTX_set_default_verify_paths(ssl_ctx))

  {

    log_errors(log, "could not set ssl context verify paths");

    goto out;

  }

  SSL_CTX_set_mode(ssl_ctx, SSL_MODE_AUTO_RETRY);

  bio = BIO_new_ssl_connect(ssl_ctx);

  if (!bio)

  {

    log_errors(log, "could not set up connection");

    goto out;

  }

  if (BIO_set_conn_port(bio, "https") <= 0)

  {

    log_errors(log, "could not set port");

    goto out;

  }

  if (!BIO_set_conn_hostname(bio, hostname))

  {

    log_errors(log, "could not set hostname");

    goto out;

  }

  BIO_get_ssl(bio, &ssl);

  if (!ssl)

  {

    log_errors(log, "could not get ssl");

    goto out;

  }

  if (!SSL_set_tlsext_host_name(ssl, hostname))

  {

    log_errors(log, "could not set sni hostname");

    goto out;

  }

  WLog_Print(log, WLOG_DEBUG, "headers:\n%s", headers);

  ERR_clear_error();

  const size_t hlen = strnlen(headers, size);

  if (hlen > INT32_MAX)

    goto out;

  if (BIO_write(bio, headers, (int)hlen) < 0)

  {

    log_errors(log, "could not write headers");

    goto out;

  }

  if (body)

  {

    WLog_Print(log, WLOG_DEBUG, "body:\n%s", body);

    if (blen > INT_MAX)

    {

      WLog_Print(log, WLOG_ERROR, "body too long!");

      goto out;

    }

    ERR_clear_error();

    if (BIO_write(bio, body, (int)blen) < 0)

    {

      log_errors(log, "could not write body");

      goto out;

    }

  }

  status = get_line(bio, buffer, sizeof(buffer));

  if (status <= 0)

  {

    log_errors(log, "could not read response");

    goto out;

  }

  // NOLINTNEXTLINE(cert-err34-c)

  if (sscanf(buffer, "HTTP/1.1 %li %*[^\r\n]\r\n", status_code) < 1)

  {

    WLog_Print(log, WLOG_ERROR, "invalid HTTP status line");

    goto out;

  }

  do

  {

    status = get_line(bio, buffer, sizeof(buffer));

    if (status <= 0)

    {

      log_errors(log, "could not read response");

      goto out;

    }

    char* val = NULL;

    char* name = strtok_s(buffer, ":", &val);

    if (name && (_stricmp(name, "content-length") == 0))

    {

      errno = 0;

      *response_length = strtoul(val, NULL, 10);

      if (errno)

      {

        char ebuffer[256] = { 0 };

        WLog_Print(log, WLOG_ERROR, "could not parse content length (%s): %s [%d]", val,

                   winpr_strerror(errno, ebuffer, sizeof(ebuffer)), errno);

        goto out;

      }

    }

  } while (strcmp(buffer, "\r\n") != 0);

  if (*response_length > 0)

  {

    if (*response_length > INT_MAX)

    {

      WLog_Print(log, WLOG_ERROR, "response too long!");

      goto out;

    }

    *response = calloc(1, *response_length + 1);

    if (!*response)

      goto out;

    BYTE* p = *response;

    size_t left = *response_length;

    while (left > 0)

    {

      const int rd = (left < INT32_MAX) ? (int)left : INT32_MAX;

      status = BIO_read(bio, p, rd);

      if (status <= 0)

      {

        log_errors(log, "could not read response");

        goto out;

      }

      p += status;

      if ((size_t)status > left)

        break;

      left -= (size_t)status;

    }

  }

  ret = TRUE;

out:

  if (!ret)

  {

    free(*response);

    *response = NULL;

    *response_length = 0;

  }

  free(hostname);

  free(headers);

  BIO_free_all(bio);

  SSL_CTX_free(ssl_ctx);

  return ret;

}

const char* freerdp_http_status_string(long status)

{

  switch (status)

  {

    case HTTP_STATUS_CONTINUE:

      return "HTTP_STATUS_CONTINUE";

    case HTTP_STATUS_SWITCH_PROTOCOLS:

      return "HTTP_STATUS_SWITCH_PROTOCOLS";

    case HTTP_STATUS_OK:

      return "HTTP_STATUS_OK";

    case HTTP_STATUS_CREATED:

      return "HTTP_STATUS_CREATED";

    case HTTP_STATUS_ACCEPTED:

      return "HTTP_STATUS_ACCEPTED";

    case HTTP_STATUS_PARTIAL:

      return "HTTP_STATUS_PARTIAL";

    case HTTP_STATUS_NO_CONTENT:

      return "HTTP_STATUS_NO_CONTENT";

    case HTTP_STATUS_RESET_CONTENT:

      return "HTTP_STATUS_RESET_CONTENT";

    case HTTP_STATUS_PARTIAL_CONTENT:

      return "HTTP_STATUS_PARTIAL_CONTENT";

    case HTTP_STATUS_WEBDAV_MULTI_STATUS:

      return "HTTP_STATUS_WEBDAV_MULTI_STATUS";

    case HTTP_STATUS_AMBIGUOUS:

      return "HTTP_STATUS_AMBIGUOUS";

    case HTTP_STATUS_MOVED:

      return "HTTP_STATUS_MOVED";

    case HTTP_STATUS_REDIRECT:

      return "HTTP_STATUS_REDIRECT";

    case HTTP_STATUS_REDIRECT_METHOD:

      return "HTTP_STATUS_REDIRECT_METHOD";

    case HTTP_STATUS_NOT_MODIFIED:

      return "HTTP_STATUS_NOT_MODIFIED";

    case HTTP_STATUS_USE_PROXY:

      return "HTTP_STATUS_USE_PROXY";

    case HTTP_STATUS_REDIRECT_KEEP_VERB:

      return "HTTP_STATUS_REDIRECT_KEEP_VERB";

    case HTTP_STATUS_BAD_REQUEST:

      return "HTTP_STATUS_BAD_REQUEST";

    case HTTP_STATUS_DENIED:

      return "HTTP_STATUS_DENIED";

    case HTTP_STATUS_PAYMENT_REQ:

      return "HTTP_STATUS_PAYMENT_REQ";

    case HTTP_STATUS_FORBIDDEN:

      return "HTTP_STATUS_FORBIDDEN";

    case HTTP_STATUS_NOT_FOUND:

      return "HTTP_STATUS_NOT_FOUND";

    case HTTP_STATUS_BAD_METHOD:

      return "HTTP_STATUS_BAD_METHOD";

    case HTTP_STATUS_NONE_ACCEPTABLE:

      return "HTTP_STATUS_NONE_ACCEPTABLE";

    case HTTP_STATUS_PROXY_AUTH_REQ:

      return "HTTP_STATUS_PROXY_AUTH_REQ";

    case HTTP_STATUS_REQUEST_TIMEOUT:

      return "HTTP_STATUS_REQUEST_TIMEOUT";

    case HTTP_STATUS_CONFLICT:

      return "HTTP_STATUS_CONFLICT";

    case HTTP_STATUS_GONE:

      return "HTTP_STATUS_GONE";

    case HTTP_STATUS_LENGTH_REQUIRED:

      return "HTTP_STATUS_LENGTH_REQUIRED";

    case HTTP_STATUS_PRECOND_FAILED:

      return "HTTP_STATUS_PRECOND_FAILED";

    case HTTP_STATUS_REQUEST_TOO_LARGE:

      return "HTTP_STATUS_REQUEST_TOO_LARGE";

    case HTTP_STATUS_URI_TOO_LONG:

      return "HTTP_STATUS_URI_TOO_LONG";

    case HTTP_STATUS_UNSUPPORTED_MEDIA:

      return "HTTP_STATUS_UNSUPPORTED_MEDIA";

    case HTTP_STATUS_RETRY_WITH:

      return "HTTP_STATUS_RETRY_WITH";

    case HTTP_STATUS_SERVER_ERROR:

      return "HTTP_STATUS_SERVER_ERROR";

    case HTTP_STATUS_NOT_SUPPORTED:

      return "HTTP_STATUS_NOT_SUPPORTED";

    case HTTP_STATUS_BAD_GATEWAY:

      return "HTTP_STATUS_BAD_GATEWAY";

    case HTTP_STATUS_SERVICE_UNAVAIL:

      return "HTTP_STATUS_SERVICE_UNAVAIL";

    case HTTP_STATUS_GATEWAY_TIMEOUT:

      return "HTTP_STATUS_GATEWAY_TIMEOUT";

    case HTTP_STATUS_VERSION_NOT_SUP:

      return "HTTP_STATUS_VERSION_NOT_SUP";

    default:

      return "HTTP_STATUS_UNKNOWN";

  }

}

const char* freerdp_http_status_string_format(long status, char* buffer, size_t size)

{

  const char* code = freerdp_http_status_string(status);

  (void)_snprintf(buffer, size, "%s [%ld]", code, status);

  return buffer;

}